<template>
  <div>
    <p><button @click="dj">控制台查看</button></p>
  </div>
</template>

<script>
export default {
  data () {
    return {
      arr: [1, 2, 3, 4, 5],
      brr: []
    }
  },
  methods: {
    dj () {
      this.copy(this.arr)
      this.arr.push(100)
      console.log(this.brr)
    },
    copy (target) {
      this.brr = [...target]
    }
  }
}
</script>

<style>
</style>